Packaging case and packaging material therefor

ABSTRACT

An object is to secure a sufficient area for bonding a spout open/close member ( 51 ). A packaging container has a pair of seal portions; at least five side-surface panel portions ( 27 ) for forming a circumferential wall; an end-surface panel portion ( 35 ) disposed between the seal portion and the side-surface panel portions ( 27 ) and adapted to form a polygonal end-surface portion in cooperation with an intermediate portion ( 15   a ) of the seal portion; and flap portions ( 31 ) projected, together with end portions ( 15   b ) of the seal portion, from the end-surface panel portion ( 35 ), each of the flap portions ( 31 ) being bent toward a specified panel portion ( 27   a ) among the side-surface panel portions ( 27 ) and being welded to the specified panel portion ( 27   a ). In this case, since the flap portions ( 31 ) are welded to the specified panel portions ( 27   a ), and the end-surface portion is thus made substantially flat, a sufficiently large flat area can be secured on the end-surface portion.

TECHNICAL FIELD

The present invention relates to a packaging container and packagingmaterial therefor.

BACKGROUND ART

Conventionally, in order to reduce the weight and cost, a packagingcontainer containing liquid food (contents) such as milk or soft drinkis manufactured from a packaging material including a paper substrateand resin layers formed so as to sandwich the paper substrate.

A method of manufacturing such packaging containers comprises a firststep of forming a semi-finished package as an intermediate product, anda second step of forming a final package.

In the first step, a sheet-shaped packaging material is transportedlongitudinally and the opposite transverse edges of the packagingmaterial are sealed together in the longitudinal direction (longitudinalsealing) so as to form the packaging material into a tubular shape, andliquid food is charged therein. Subsequently, the tubular packagingmaterial is sealed in a transverse direction (transverse sealing) atpredetermined intervals in order to form strip-shaped sealed portions,and is then cut at the sealed portions. Thus is formed a pillow-shaped,semi-finished package that contains liquid food and has a predeterminedthickness.

In the second step, the semi-finished package is formed into a polygonalcolumnar shape such as a hexagonal prism or an octagonal prism, and apair of flaps are formed at either end of the semi-finished package.Subsequently, the flaps at either end are folded so as to face eachother and welded to the corresponding end-surface portion to completethe final package (see Japanese Patent Application Laid-Open (kokai) No.7-187181).

A rupturable portion is formed in advance in the upper end-surfaceportion of the final package. The rupturable portion is easily rupturedupon receipt of an external force. Further, a spout open/close memberformed of a resin is bonded to the final package at a positioncorresponding to the rupturable portion. In this manner, a packagingcontainer is formed.

However, in such a packaging container, since two flaps are welded tothe upper end-surface portion, it is difficult to secure a sufficientlylarge area where the spout open/close member is bonded. Therefore, thebonding area between the spout open/close member and the upperend-surface portion decreases, resulting in failure to bond the spoutopen/close member with sufficient adhesion force. In addition, sinceprojections and depressions are formed on the upper end-surface portion,the appearance of the packaging container deteriorates. Moreover, if thespout open/close member is bonded to a narrow area, the spout open/closemember becomes difficult to operate, with the result that the packagingcontainer cannot be opened with ease.

A large-sized spout open/close member that covers the entire upperend-surface portion may be used. However, in this case, the degree offreedom in designing the size, shape, etc., of the spout open/closemember decreases.

An object of the present invention is to solve the problems involved inconventional packaging containers and to provide a packaging containerand packaging material therefor which can secure a sufficient area forbonding a spout open/close member, which enable the spout open/closemember to be bonded with sufficient adhesion force, which i provide animproved appearance, and which increase the degree of freedom indesigning the spout open/close member.

DISCLOSURE OF THE INVENTION

To achieve the above object, a packaging container according to thepresent invention comprises: a pair of seal portions; at least fiveside-surface panel portions for forming a circumferential wall; anend-surface panel portion disposed between the seal portion and theside-surface panel portions and adapted to form a polygonal end-surfaceportion in cooperation with an intermediate portion of the seal portion;and flap portions projected, together with end portions of the sealportion, from the end-surface panel portion, each of the flap portionsbeing bent toward a specified panel portion among the side-surface panelportions and-being welded to the specified panel portion.

In this case, since the flap portions are welded to the specified panelportions, and the end-surface portion is thus made substantially flat, asufficiently large flat area can be secured on the end-surface portion.Since no projection or depression is formed on the end-surface portion,the appearance of the packaging container can be improved, and asufficiently large area for bonding the spout open/close member can besecured.

Further, the bonding area between the spout open/close member and theend-surface portion can be increased without use of a large spoutopen/close member that covers the entire end-surface portion, so thatthe spout open/close member can be bonded with sufficient adhesionforce. Moreover, since the end-surface portion is not prone toaccumulation of dust, the packaging container is sanitary. In addition,the appearance of the packaging container can be improved, and thedegree of freedom in designing the size, shape, etc., of the spoutopen/close member can be increased.

Another packaging container according to the present invention furthercomprises a first folding portion formed between each of the flapportions and corresponding one of the specified panel portions, and asecond folding portion formed between the end-surface panel portion andeach side-surface panel portion adjacent to each of the specified panelportions.

In still another packaging container according to the present invention,each of the first and second folding portions has a lower foldingportion formed adjacent to the side-surface panel portion and beingsuperposed on the side-surface panel portion, as well as an upperfolding portion formed adjacent to the lower folding portion and beingsuperposed on the lower folding portion.

In still another packaging container according to the present invention,the upper folding portion and the lower folding portion of the firstfolding portion each have a rectangular shape, and the upper foldingportion and the lower folding portion of the second folding portion eachhave a triangular shape.

In still another packaging container according to the present invention,crush portions are formed in regions surrounded by the flap portions,the upper folding portions of the first folding portions, and the upperfolding portions of the second folding portions, and the crush portionsare crushed when the flap portions are bent toward the specified panelportions.

In this case, since the crush portions are crushed when the flapportions are bent toward the specified panel portions, the upper endportions of the flap portions do not project far from the side-surfacepanel portions. Accordingly, the appearance of the packaging containercan be improved.

A packaging material for a packaging container according to the presentinvention comprises: a pair of seal portions; at least five side-surfacepanel portions for forming a circumferential wall; an end-surface panelportion disposed between the seal portion and the side-surface panelportions and adapted to form a polygonal end-surface portion incooperation with an intermediate portion of the seal portion; and flapportions projected, together with end portions of the seal portion, fromthe end-surface panel portion, each of the flap portions being benttoward a specified panel portion among the side-surface panel portionsand being welded to the specified panel portion.

Another packaging material for a packaging container according to thepresent invention further comprises a first folding portion formedbetween each of the flap portions and corresponding one of the specifiedpanel portions, and a second folding portion formed between theend-surface panel portion and each side-surface panel portion adjacentto each of the specified panel portions.

In still another packaging material for a packaging container accordingto the present invention, each of the first and second folding portionshas a lower folding portion formed adjacent to the side-surface panelportion and being superposed on the side-surface panel portion, as wellas an upper folding portion formed adjacent to the lower folding portionand being superposed on the lower folding portion.

In still another packaging material for a packaging container accordingto the present invention, the upper folding portion and the lowerfolding portion of the first folding portion each have a rectangularshape, and the upper folding portion and the lower folding portion ofthe second folding portion each have a triangular shape.

In still another packaging material for a packaging container accordingto the present invention, crush portions are formed in regionssurrounded by the flap portions, the upper folding portions of the firstfolding portions, and the upper folding portions of the second foldingportions, and the crush portions are crushed when the flap portions arebent toward the specified panel portions.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a development of a packaging material used in an embodiment ofthe present invention;

FIG. 2 is a perspective view of a semi-finished package in theembodiment of the present invention;

FIG. 3 is a first view showing a method of forming a final package inthe embodiment of the present invention;

FIG. 4 is a second view showing the method of forming the final packagein the embodiment of the present invention;

FIG. 5 is a view showing a state in which a spout open/close member isattached to the final package in the embodiment of the presentinvention;

FIG. 6 is a perspective view of the final package in the embodiment ofthe present invention as viewed from the bottom thereof;

FIG. 7 is a first view of a main portion of the final package showingthe manner of forming the final package in the embodiment of the presentinvention;

FIG. 8 is a second view of the main portion of the final package showingthe manner of forming the final package in the embodiment of the presentinvention; and

FIG. 9 is a third view of the main portion of the final package showingthe manner of forming the final package in the embodiment of the presentinvention.

BEST MODE FOR CARRYING OUT THE INVENTION

An embodiment of the present invention will next be described in detailwith reference to the drawings.

FIG. 1 is a development of a packaging material used in the embodimentof the present invention; FIG. 2 is a perspective view of asemi-finished package in the embodiment of the present invention; FIG. 3is a first view showing a method of forming a final package in theembodiment of the present invention; FIG. 4 is a second view showing themethod of forming the final package in the embodiment of the presentinvention; FIG. 5 is a view showing a state in which a spout open/closemember is attached to the final package in the embodiment of the presentinvention; and FIG. 6 is a perspective view of the final package in theembodiment of the present invention as viewed from the bottom thereof.

A packaging material 30 is formed by a method in which a resin isapplied or layered onto the surface of an unillustrated paper substrate.In a developed state, a region for forming one packaging container isdefined between upper and lower cutting lines 16 and 18, which areformed to extend transversely. The region is divided by means of creases(shown by chain lines in FIG. 1) so as to form transverse seal portions15 and 17, end-surface panel portions 35 and 43, flap portions 31 and 33first and second folding portions 37 and 39, crush portions 41, primarybending portions 45, secondary bending portions 47, and side-surfacepanel portions 27.

Next, a method of manufacturing a packaging container will be described.

The method of manufacturing a packaging container comprises a first stepof forming a semi-finished package (an intermediate product) 50 shown inFIG. 2 from the sheet-shaped packaging material 30 shown in FIG. 1; anda second step of forming a final package 70 shown in FIG. 5 from thesemi-finished package 50 shown in FIG. 2.

In the first step, the packaging material 30 in a rolled state isunwound into a form of web. Longitudinal seal portions 11 and 13 formedat opposite transverse edges of the web-shaped packaging material 30 aresuperposed on each other and sealed together in a longitudinaldirection, so that the packaging material 30 is formed into a tubularshape. Subsequently, liquid food is charged into the tubular packagingmaterial 30, and the tubular packaging material 30 is sealed atstrip-shaped transverse seal portions 15 and 17 provided atpredetermined intervals.

The packaging material 30 has previously-defined regions for productionof packaging containers. The transverse seal portion 15 is located atthe upper end of each region and the transverse seal portion 17 islocated at the lower end of each region. Cutting lines 16 and 18 aredefined at positions between the upper-end transverse seal portion 15 ofeach region and the lower-end transverse seal portion 17 of the adjacentregion.

Subsequently, the tubular packaging material 30 is cut along the cuttinglines 16 and 18, so that a pillow-shaped, semi-finished package 50 isformed.

In the second step, the semi-finished package 50 is formed into, forexample, an octagonal prism, so that the semi-finished package 50 has anoctagonal cross section. At this time, two flap portions 31 formed atone end of the semi-finished package 50, which corresponds to the upperend of a packaging container, and two flap portions 33 formed at theopposite end of the semi-finished package 50, which corresponds to thelower end of the packaging container, are forced to project outward.Subsequently, as shown in FIG. 5, the flap portions 31 are bent outwardand welded to the corresponding side-surface panel portions 27, and asshown in FIG. 6, the flap portions 33 are bent inward and welded to thebottom end surface. Thus, the final package 70 is formed. The details ofthe second step will be described later.

Next, the structure of the packaging container will be described.

In the packaging material 30, the semi-finished package 50, and thefinal package 70, there are defined an upper end-surface region 21, alower end-surface region 23, and a side surface region 25. The sidesurface region 25 has eight rectangular side-surface panel portions 27that are to form respective side surfaces of the packaging container.

The end-surface region 21 is composed of an end-surface panel portion35, two flap portions 31, two first folding portions 37, four secondfolding portions 39, and four crush portions 41.

In the final package 70, the end-surface panel portion 35, together withan intermediate portion 15 a of the transverse seal portion 15, forms anupper end-surface portion having an octagonal shape. A perforation 36 ais formed in the upper end-surface portion in order to define arupturable portion 36 at a position other than those of the longitudinalseal portions 11 and 13 and the transverse seal portion 15. Therupturable portion 36 enable easy opening of the packaging container.

When the semi-finished package 50 is formed into an octagonal prism,each flap portion 31, together with an end portion 15 b of thetransverse seal portion 15, is projected from the end-surface panelportion 35 (a side of the side-surface panel portion 27), and assumes asubstantially triangular shape. Each flap portion 31 is located adjacentto each of two opposed specified panel portions 27 a among theside-surface panel portions 27 as well as to the end-surface panelportion 35. The flap portions 31 are bent toward the specified panelportions 27 a and are welded thereto.

Each of the first folding portions 37 is formed between thecorresponding flap portion 31 and the. specified panel portion 27 a, andeach of the second folding portions 39 is formed between the end-surfacepanel portion 35 and each side-surface panel portion 27 b adjacent tothe specified panel portions 27 a. Each of the first folding portions 37has a lower folding portion 37 a that is superposed on the specifiedpanel portion 27 a, as well as an upper folding portion 37 b that issuperposed on the lower folding portion 37 a. Each of the first foldingportions 39 has a lower folding portion 39 a that is superposed on theside-surface panel portion 27 b, as well as an upper folding portion 39b that is superposed on the lower folding portion 39 a. The lowerfolding portion 37 a and the upper folding portion 37 b of each firstfolding portion 37 each have a rectangular shape, and the lower foldingportion 39 a and the upper folding portion 39 b of each second foldingportion 39 each have a triangular shape. Therefore, when the flapportions 31 are bent toward the specified panel portions 27 a throughfolding of the first and second folding portions 37 and 39, theend-surface panel portion 35 becomes substantially flat. The crushportions 41 are formed in regions surrounded by the flap portions 31,the first folding portions 37, and the second folding portions 39 andeach have a triangular shape.

Meanwhile, the lower end-surface region 23 is composed of theend-surface panel portion 43, two flap portions 33, and primary bendingportions 45 and secondary bending portions 47 formed on opposite sidesof each of the flap portions 33.

In the final package 70 shown in FIG. 6, the end-surface panel portion43, together with an intermediate portion 17 a of the transverse sealportion 17, forms a lower end-surface portion having an octagonal shape.

When the semi-finished package 50 is formed into an octagonal prism,each flap portion 33, together with an end portion 17 b of thetransverse seal portion 17, is projected from the end-surface panelportion 43 (a side of the side-surface panel portion 27), and assumes asubstantially pentagonal shape. Each flap portion 33 is located adjacentto one of the specified panel portions 27 a as well as to the lowerend-surface portion. The flap portions 33 are bent toward the lowerend-surface portion and are welded thereto.

The above-described primary and secondary bending portions 45 and 47 areformed in regions surrounded by the end-surface panel portion 43, theflap portions 33, and the side-surface panel portions 27 b.

Next, the second step will be described in detail.

FIG. 7 is a first view of a main portion of the final package showingthe manner of forming the final package in the embodiment of the presentinvention; FIG. 8 is a second view of the main portion of the finalpackage showing the manner of forming the final package in theembodiment of the present invention; and FIG. 9 is a third view of themain portion of the final package showing the manner of forming thefinal package in the embodiment of the present invention.

As described above, in the second step, the semi-finished package 50 isformed into an octagonal prism such that the semi-finished package 50has an octagonal cross section. At this time, the flap portions 31 and33 are projected.

In the upper end-surface region 21, after the flap portions 31 areprojected outward as shown-in FIG. 7, the lower folding portions 37 aand 39 a of the first and second folding portions 37 and 39 are foldedonto the specified panel portions 27 a and the side-surface panelportions 27 b, respectively, so that, as shown in FIG. 8, the lowerfolding portions 37 a and 39 a are covered by the upper folding portions37 b and 39 b, respectively. Therefore, the upper end-surface portionbecomes substantially flat.

Subsequently, as shown in FIG. 9, the flap portions 31 are bent towardthe specified panel portions 27 a, and resin at the surface of the flapportions 31 and resin at the surface of the specified panel portions 27a are heated at a contact portion therebetween, so that the flapportions 31 are welded to the specified panel portions 27 a.

At this time, since crush portions 41 are crushed, the upper endportions (base end portions) of the flap portions 31 do not project farfrom the specified panel portions 27 a. Subsequently, a spout open/closemember 51 formed of resin is bonded to the above-described rupturableportion 36 (FIG. 5).

Meanwhile, in the lower end-surface region 23, as shown in FIG. 6, theprimary bending portions 45 and the secondary bending portions 47(FIG. 1) are folded, and the flap portions 33 are bent toward the lowerend-surface portion. Subsequently, resin at the surface of the flapportions 33 and resin at the surface of the lower end-surface portionare heated at a contact portion therebetween, so that the flap portions33 are welded to the lower end-surface portion.

As described above, in the upper end-surface region 21, the flapportions 31 are welded to the specified panel portions 27 a, and thefirst and second folding portions 37 and 39 are folded to make the upperend-surface portion substantially flat, so that a sufficiently largeflat area can be secured on the upper end-surface portion. Since noprojection or depression is formed on the upper end-surface portion, theappearance of the packaging container can be improved, and asufficiently large area for bonding the spout open/close member 51 canbe secured.

Further, the bonding area between the spout open/close member 51 and theupper end-surface portion can be increased without use of a large spoutopen/close member that covers the entire upper end-surface portion, sothat the spout open/close member 51 can be bonded with sufficientadhesion force. Moreover, since the upper end-surface portion is notprone to accumulation of dust, the packaging container is sanitary. Inaddition, the appearance of the packaging container can be improved, andthe degree of freedom in designing the size, shape, etc., of the spoutopen/close member 51 can be increased.

Since the crush portions 41 are crushed when the flap portions 31 arebent toward the specified panel portions 27 a, the upper end portions ofthe flap portions 31 do not project far from the specified panelportions 27 a. Accordingly, the appearance of the packaging containercan be improved.

Although in the embodiment only the upper end-surface portion of thepackaging container is made flat, the lower end-surface portion may alsobe made flat.

Further, although in the embodiment a packaging container having anoctagonal shape is described, the present invention is applicable topackaging containers having the shape of a pentagonal prism or ahigher-order polygonal prism.

The present invention is not limited to the above-described embodiments.Numerous modifications and variations of the present invention arepossible in light of the spirit of the present invention, and they arenot excluded from the scope of the present invention.

INDUSTRIAL APPLICABILITY

The present invention is applicable to a packaging containermanufacturing apparatus for manufacturing packaging containers.

What is claimed is:
 1. A packaging container comprising: (a) a pair ofseal portions; (b) a plurality of rectangular side-surface panelportions of the same size and forming a tube having a circumferentialwall right polygonal in cross-section: (c) a pair of end-surface panelportions disposed between one of said seal portions and saidside-surface panel portions and forming a right polygonal end-surfaceportion, in cooperation with an intermediate portion of said one sealportion, closing one end of said tube, one of said end-surface portionshaving a weakened rupturable portion; (d) flap portions projecting,together with an end portion of said one seal portion, from saidend-surface panel portions, each of said flap portions being bent ontoone of said side-surface panel portions and being welded to said oneside-surface panel portion; and (e) a pair of folding portionsrespectively connecting each one of said flap portions to two of saidside-surface panel portions contiguous with a third side-surface panelportion therebetween.
 2. A packaging container according to claim 1,further comprising: a second pair of end-surface panel portions disposedbetween a second of said seal portions and said side-surface panelportions and forming a polygonal end-surface portion, in cooperationwith an intermediate portion of said second seal portion, closing asecond end of said tube.
 3. A packaging container according to claim 1,wherein each of said folding portions has upper and lower foldingportions, said upper folding portion being superposed on said lowerfolding portion.
 4. A packaging container according to claim 3, wherein(a) the-upper folding portion and the lower folding portion of saidfirst folding portion each have a rectangular shape; and (b) the upperfolding portion and the lower folding portion of said second foldingportion each have a triangular shape.
 5. A packaging container accordingto claim 3, further comprising: crushed portions formed in regionssurrounded by said flap portions, the upper folding portions of saidfirst folding portions, and the upper folding portions of said secondfolding portions.
 6. A packaging container according to claim 1 whereineach one of said flap portions is connected to said third side-surfacepanel portion through a third folding portion.
 7. A packaging materialfor forming a packaging container comprising: (a) a pair of sealportions; (b) a plurality of rectangular side-surface panel portions ofthe same size and joined directly to each other in series for forming acircumferential wall of a tube; (c) a pair of end-surface panel portionsdisposed between one of said seal portions and said side-surface panelportions and adapted to form a right polygonal end-surface portion, incooperation with an intermediate portion of said one, seal portion, toclose one end of the tube, one of said end-surface portions having aweakened rupturable portion; (d) flap portions foldable, together withan end portion of said seal portion, to project from said end-surfacepanel portions, each of said flap portions being positioned adjacent tosaid end-surface panel portions for bending onto one of saidside-surface panel portions, for welding to said one side-surface panelportion; and (e) a pair of folding portions respectively connecting eachone of said flap portions to two of sad side-surface panel portionscontiguous with a third side-surface panel portion therebetween.
 8. Apackaging material for a packaging container according to claim 6,wherein each of said folding portions has upper and lower foldingportions, said upper folding portion being foldable onto said lowerfolding portion.
 9. A packaging material for a packaging containeraccording to claim 8, wherein (a) the upper folding portion and thelower folding portion of said first folding portion each have arectangular shape; and (b) the upper folding portion and the lowerfolding portion of said second folding portion each have a triangularshape.
 10. A packaging material for a packaging container according toclaim 8, further comprising: crushable portions in regions surrounded bysaid flap portions, the upper folding portions of said first foldingportions, and the upper folding portions of said second foldingportions, said crushable portions being crushed when said flap portionsare bent toward said one side-surface panel portion.
 11. A packagingcontainer according to claim 7 wherein each one of said flap portions isconnected to said third side-surface panel portion through a thirdfolding portion.
 12. A packaging material for forming a containeraccording to claim 7, further comprising: a second pair of end-surfacepanel portions disposed between a second of said seal portions and saidside-surface panel portions and adapted to form a polygonal end-surfaceportion in cooperation with an intermediate portion of said second sealportion to close a second end of the tube.